This is design work of a Ring which can be prepared with different colored sort of gems. White gems are diamonds. On a pictures You can review the prepared version in gold 18k with diamonds.
Also watch the video of the ring with blue and red central gems.
The max weight for 18k is approx 12 gr (only metal weight) The total weight of gems is approx 0.8 ct (white diamonds)The weight of central big Colored gem is approx 6-8 ct